Pulley construction, drive system utilizing the same and methods of making the same

ABSTRACT

A pulley construction, drive system utilizing the pulley construction and method of making the pulley construction are provided, the pulley construction being utilized with an endless drive belt and comprising a body member having a peripheral groove therein for receiving part of the belt therein and having a securing unit, and a hub member having a securing unit secured to the securing unit of the body member so as to hold the members in aligned assembled relation to rotate in unison, the hub member having structure for being interconnected to a shaft so that the pulley construction and the shaft will be adapted to rotate in unison, the securing units are so constructed and arranged that the securing unit of one of the members has as part thereof that is adapted to break away from the one member under a certain normal driving force of the belt when the shaft is prevented from rotating so as to permit relative rotational movement between the members while the securing units maintain the thus relatively rotatable members in the aligned assembled relation thereof.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a new pulley construction for use with anendless drive belt means and to a method of making the same, as well asto a new drive system utilizing such a pulley construction.

2. Prior Art Statement

It is known to provide a pulley construction for use with an endlessdrive belt means, the pulley construction comprising a body memberhaving a peripheral groove means therein for receiving part of the beltmeans therein and having securing means, and a hub member havingsecuring means secured to the securing means of the body member so as tohold the members in aligned assembled relation to rotate in unison, thehub member having means for being interconnected to a shaft means sothat the pulley construction and the shaft means will be adapted torotate in unison. For example, see the U.S. Pat. to Heinish, No.2,674,897, the U.S. Pat. to Cigala et al, No. 3,788,155, the U.S. Pat.to Speer, No. 4,366,609, the U.S. Pat. to St. John, No. 4,402,678 andthe U.S. Pat. to McCutchan, Jr., No. 4,473,363.

SUMMARY OF THE INVENTION

It is one feature of this invention to provide a new pulley constructionfor use with an endless drive belt means wherein the body member of thebelt construction will continue to operate in the drive system eventhough a component that was to be driven by that pulley construction hasfailed in a manner that tends to prevent rotation of the shaft meansthereof.

In particular, it was found according to the teachings of this inventionthat when a component of a belt drive system seizes so that the endlessbelt means cannot rotate the same through a pulley construction that isinterconnected to the shaft means thereof, the entire drive system isprevented from operating properly.

Therefore, it is believed according to the teachings of this inventionthat a pulley construction can be so constructed and arranged that thebody member thereof can break away from the hub member thereof under acertain normal driving force of the belt means if the hub member isprevented from rotating in unison therewith whereby the body member canbe driven by the belt means relative to the hub member.

For example, one embodiment of this invention provides a pulleyconstruction for use with an endless drive belt means, the pulleyconstruction comprising a body member having a peripheral groove meanstherein for receiving part of the belt means therein and having securingmeans, and a hub member having securing means secured to the securingmeans of the body member so as to hold the members in aligned assembledrelation to rotate in unison, the hub member having means for beinginterconnected to a shaft means so that the pulley construction and theshaft means will be adapted to rotate in unison, the securing meansbeing so constructed and arranged that the securing means of one of themembers has a part thereof that is adapted to break away from the onemember under a certain normal driving force of the belt means when theshaft means is prevented from rotating so as to permit relativerotational movement between the members while the securing meansmaintains the thus relatively rotatable members in the aligned assembledrelation thereof.

Accordingly, it is an object of this invention to provide a new pulleyconstruction for use with an endless drive belt means, the pulleyconstruction of this invention having one or more of the novel featuresof this invention as set forth above or hereinafter shown or described.

Another object of this invention is to provide a new drive systemutilizing such a pulley construction, the drive system of this inventionhaving one or more of the novel features of this invention as set forthabove or hereinafter shown or described.

Another object of this invention is to provide a new method of makingsuch a pulley construction, the method of this invention having one ormore of the novel features of this invention as set forth above orhereinfter shown or described.

Other objects, uses and advantages of this invention are apparent from areading of this description which proceeds with reference to theaccompanying drawings forming a part thereof and wherein:

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a top view of the drive system of this invention.

FIG. 2 is an enlarged fragmentary perspective view of a part of thedrive system of FIG. 1 and illustrates the one embodiment of the newpulley construction of this invention.

FIG. 3 is a front view of the pulley construction of FIG. 2.

FIG. 4 is a cross-sectional view taken on line 4--4 of FIG. 3.

FIG. 5 is a front view of the hub member of the pulley construction ofFIG. 3.

FIG. 6 is an enlarged fragmentary cross-sectional view taken on line6--6 of FIG. 3.

FIG. 7 is a view similar to FIG. 6 and illustrates the pulleyconstruction after the body member has its securing means broken away bythe securing means of the hub member.

FIG. 8 is a view similar to FIG. 3 and illustrates another embodiment ofthe pulley construction of this invention.

FIG. 9 is a front view of the hub member of the pulley construction ofFIG. 8.

FIG. 10 is an enlarged fragmentary cross-sectional view taken on line10--10 of FIG. 8.

FIG. 11 is a view similar to FIG. 10 and illustrates the pulleyconstruction after the securing means of the body member has been brokenaway by the securing means of the hub member.

FIG. 12 is a view similar to FIG. 3 and illustrates another embodimentof the pulley construction of this invention.

FIG. 13 is a front view of the hub member of the pulley construction ofFIG. 12.

FIG. 14 is an enlarged fragmentary cross-sectional view taken on line14--14 of FIG. 12.

FIG. 15 is a view similar to FIG. 14 and illustrates the pulleyconstruction after the securing means of the body member has been brokenaway by the securing means of the hub member.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

While the various features of this invention are hereinafter illustratedand described as being particularly adapted to provide a pulleyconstruction for use in a drive system for the components of an internalcombustion engine of a transportation vehicle, it is to be understoodthat the various features of this invention can be utilized singly or invarious combinations thereof to provide a pulley construction for use inthe drive systems of other types of apparatus as desired.

Therefore, this invention is not to be limited to only the embodimentsillustrated in the drawings, because the drawings are merely utilized toillustrate one of the wide variety of uses of this invention.

Referring now to FIGS. 1 and 2, the new drive system of this inventionis generally indicated by the reference numeral 20 and comprises a drivemeans 21 having an output shaft 22 that rotatably drives a pulleyconstruction 23 in a conventional manner so that the drive pulley 23will move an endless belt means 24 through an endless path and therebyrotatably drive components of the system 20, such as the component 25that has its shaft means 26 interconnected to a pulley construction 27of this invention that is driven by the endless belt means 24 in aconventional manner.

For example, the drive system 20 can be utilized on an internalcombustion engine (not shown) of a transportation vehicle wherein thedrive means 21 is provided by the internal combustion engine thereof andthe component 25 could be an air pump, an alternator, water pump etc, ofthe arrangement, the drive system 20 obviously including one or morecomponents 25 to be driven by the same belt means 24 in a mannerconventional in the art.

As previously stated, it is one feature of this invention to provide thepulley construction 27 of this invention with means that permits thesystem 20 to continue to operate in substantially a normal manner eventhough the component 25 should fail in some manner so that the shaftmeans 26 thereof cannot rotate. For example, the component 25 may seize,have a bearing failure or otherwise lock up so that a non-modifiedpulley construction could not be rotatably driven by the belt means 24even though the drive means 21 is continuously operating to drive thebelt means 24 in a continuous manner whereby the belt means 24 would rubon the thus non-rotating pulley construction.

The pulley construction 27 of this invention accomplishes the abovecontinuously operating feature by unique structure thereof now to bedescribed.

The pulley construction 27 of this invention comprises a body member 28that has a peripheral groove means 29 formed in the outer peripheralportion 30 thereof for receiving part of the endless belt means 24therein for rotating the pulley construction 27 as the belt means 24 isbeing continuously moved by the drive means 21, such as in the directionof the arrow 31 in FIG. 2.

The body member 28 of the pulley construction 27 has an inner peripheralportion 32 that is secured to an outer peripheral portion 33 of a hubmember 34 of the pulley construction 27 in a manner hereinafter setforth so that the members 28 and 34 are adapted to normally rotate inunison.

The hub member 34 is provided with means 35 in the inner peripheralportion 36 thereof for securing to the shaft means 26, such as by thenut 37 and washer 38 arrangement illustrated in FIG. 2 or throughsuitable bolt openings 39 in a conventional manner, the shaft means 26projecting through a central opening 40 in the hub member 34 in aconventional manner.

In any event, the shaft means 26 is adapted to be interconnected to theinner peripheral portion 36 of the hub member 34 so that as the pulleyconstruction 27 is rotated by the moving belt means 24, the shaft means26 will rotate in unison therewith and thereby drive the drivencomponent 25.

While the body member 28 and hub member 34 of the pulley construction 27of this invention can be formed of any suitable material in any suitablemanner, the body member 28 is formed of polymeric material, such as arigid plastic material, that is molded to the hub member 34 in theconfiguration thereof as illustrated in the drawings while the hubmember 34 comprises a substantially flat metal plate that has opposedflat sides 41 and 42 that are disposed parallel to each other andrespectively terminate at an outer peripheral edge means 43 of the hubmember 34 that is substantially circular and concentric to the centralopening 40 thereof as illustrated.

The body member 28 has securing means that is generally indicated by thereference numeral 44 and is secured to securing means 45 of the hubmember 34 so that normally the body member 28 and hub member 34 areadapted to rotate in unison. However, the securing means 44 and 45 areso constructed and arranged in a manner hereinafter set forth thatshould the shaft means 26 seize or otherwise prevent the pulleyconstruction 27 from rotating in a normal manner during a normal drivingoperation of the belt means 24 by the drive means 21, at least one ofthe securing means 44 or 45 will break away so as to permit the bodymember 28 to freely rotate on the non-rotating hub member 34 in alignedassembled relation therewith and thereby permit the drive system 20 tokeep functioning in substantially a normal manner even though thecomponent 25 is in a failed condition thereof so that the belt means 24can continue to drive the other components of the system 20 aspreviously set forth and not have the belt means rub on a non-rotatingpulley construction.

The securing means 44 of the body member 28 comprises an internalperipheral slot means that is generally indicated by the referencenumeral 46 in FIG. 6 and interrupts the internal peripheral edge 47thereof to define spaced apart facing sides 48 and 49 that are disposedagainst the facing sides 41 and 42 of the outer peripheral portion 33 ofthe hub member 34 so as to hold the hub member 34 in aligned relationtherewith but being adapted to slide relative thereto as will beapparent hereinafter. However, the securing means 44 of the body member28 also comprises a plurality of parts 50 of the body member 28 thatrespectively project through a plurality of spaced apart openings 51 ofthe hub member 34 which extend through the opposed sides 41 and 42thereof at the outer peripheral portion 33 thereof and comprise thesecuring means 45 thereof, the parts 50 being formed at the same timethat the body member 28 is being molded on the hub member 34.

In this manner, the parts 50 of the body member 28 are normally integraland one-piece therewith and because the same are disposed in theopenings 51 of the hub member 34, the parts 50 cause the hub member 34to move in unison with the body member 28 during the normal operation ofthe pulley construction 27.

However, it is believed that the size and number of the openings 51 aswell as the particular material forming the body member 28 can be soselected that when the component 25 of the pulley construction 27 seizesor otherwise causes the shaft means 26 thereof to stop rotating eventhough the drive system 21 is moving the endless belt 24 in a normaldriving manner thereof, the normal driving force of the belt means 24will cause the hub member 28 to have the parts 50 thereof shear awayfrom the inner peripheral portion 32 thereof in the manner illustratedin FIG. 7 and thereby now only be carried in the openings 51 of the hubmember 34 so that the body member 28 can rotate relative to the hubmember 34 and remain in aligned assembled relation therewith as the bodymember 28 maintains the outer peripheral portion 33 of the hub member 34within the slot means 46 thereof as illustrated so that the body member28 can freely rotate on the now non-rotating hub member 34 and therebypermit substantially normal operation of the drive system 20.

While the securing means 45 of the hub member 34 is illustrated as aplurality of opening means 51 disposed in a spaced apart circular arraythereof and each having a substantially circular configuration asillustrated in FIG. 5, it is to be understood that the securing means 44and 45 of the body member 28 and hub member 34 can be of otherconfigurations and in other locations to perform in the mannerpreviously set forth.

For example, another pulley construction of this invention is generallyindicated by the reference numeral 27A in FIGS. 8-11 and parts thereofsimilar to the pulley construction 27 previously described are indicatedby like reference numerals followed by the reference letter "A".

As illustrated in FIGS. 8-11, the pulley construction 27A is formed ofthe body member 28A and the hub member 34A with each being formed insubstantially the same manner as the body member 28 and hub member 34 aspreviously set forth. However, the securing means 45A of the hub member34A comprises a plurality of notches 51' that interrupt the outerperipheral edge 43A thereof, the number of notches 51' being anysuitable number thereof and being uniformly spaced apart as illustratedin FIG. 9.

In this manner, the interconnecting or securing means 44A of the bodymember 28A comprises a plurality of parts 52 that normally extend intothe notches 51' and are integral and one-piece with the inner peripheralportion 32A of the body member 28A as illustrated in FIG. 10, the parts52 having been formed into the notches 51' at the same time that thebody member 28A is being molded on the hub member 34A.

However, when the hub member 34A is prevented from rotating in unisonwith the body member 28A for the reasons previously set forth, the parts52 of the body member 28A break away from the same and are carried inthe notches 51' of the hub member 34A as illustrated in FIG. 11 so thatthe body member 28A can freely rotate relative to the non-rotating hubmember 34A in aligned relation therewith as the hub member 34A remainsin the slot 46A of the body member 28A as illustrated.

Another pulley construction of this invention is generally indicated bythe reference numeral 27B in FIGS. 12-15 and parts thereof similar tothe parts of the pulley construction 27 previously described areindicated by like reference numerals followed by the reference letter"B".

The pulley construction 27B of FIGS. 12-15 is substantially the same asthe pulley construction 27 previously described except that the securingmeans 45B of the hub member 34B comprise elongated substantiallyrectangular openings 53 that are arcuate and disposed in the spacedapart circular array thereof and respectively receive integral parts 54of the body member 28B therein in the manner illustrated in FIG. 14 sothat the parts 54 are adapted to shear away from the hub member 34B andpermit the body member 28B to rotate relative thereto in the mannerillustrated in FIG. 15 for the reasons previously set forth.

Therefore, it can be seen that the securing means of the body member andhub member of the pulley construction of this invention can take variousforms thereof which readily permit the body member to break away fromthe hub member under a certain normal driving force of a belt means whenthe shaft means carrying the hub member is prevented from rotating so asto permit relative rotational movement between the body member and thehub member while the securing means thereof maintains the relativelyrotatable members in the aligned assembled relation thereof.

While each pulley construction of this invention has been illustratedand described as having a part of the securing means of the body memberbe broken away by the hub member, it is to be understood that the hubmember could have a part of the securing means thereof break away fromthe body member or that both securing means of the body member and thehub member could be arranged to break away to permit the body member torotate on the hub member, as desired.

Also, while the pulley construction 27 has been described as being adriven pulley construction so that the body member breaks away from thehub thereof when the hub member is prevented from rotating, it is to beunderstood that should a pulley construction of this invention beutilized as a drive pulley construction, the hub member thereof isadapted to break away from the body member thereof should the bodymember thereof be prevented from rotating so that the hub member canrotate relative to the now stationary body member for the reasonspreviously set forth.

Therefore, it can be seen that this invention not only provides a newpulley construction for use with an endless drive belt means and to anew method of making such a pulley construction, but also this inventionprovides a new drive system utilizing such a pulley construction.

While the forms and methods of this invention now preferred have beenillustrated and described as required by the Patent Statute, it is to beunderstood that other forms and method steps can be utilized and stillfall within the scope of the appended claims wherein each claim setsforth what is believed to be known in each claim prior to this inventionin the portion of each claim that is disposed before the terms "theimprovement" and sets forth what is believed to be new in each claimaccording to this invention in the portion of each claim that isdisposed after the terms "the improvement" whereby it is believed thateach claim sets forth a novel, useful and unobvious invention within thepurview of the Patent Statute.

What is claimed is:
 1. In a pulley construction for use with an endlessdrive belt means, said pulley construction comprising a body memberhaving a peripheral groove means therein for receiving part of said beltmeans therein and having securing means, and a hub member havingsecuring means secured to said securing means of said body member so asto hold said members in aligned assembled relation to rotate in unison,said hub member having means for being interconnected to a shaft meansso that said pulley construction and said shaft means will be adapted torotate in unison, the improvement wherein said securing means are soconstructed and arranged that said securing means of one of said membershas a part thereof that is adapted to break away from said one memberunder a certain normal driving force of said belt means when said shaftmeans is prevented from rotating so as to permit relative rotationalmovement between said members while said securing means maintains thethus relatively rotatable members in said aligned assembled relationthereof.
 2. A pulley construction as set forth in claim 1 wherein saidsecuring means of said other member comprises opening means passingtherethrough, said part of said securing means of said one memberextending through said opening means.
 3. A pulley construction as setforth in claim 2 wherein said part of said securing means of said onemember is integral and one-piece with said one member.
 4. A pulleyconstruction as set forth in claim 3 wherein said one member is formedof rigid polymeric material.
 5. A pulley construction as set forth inclaim 4 wherein said one member comprises said body member.
 6. A pulleyconstruction as set forth in claim 2 wherein said opening means of saidother member comprises a plurality of spaced apart openings and saidpart of said securing means of said one member comprises a plurality ofparts respectively extending through said openings.
 7. A pulleyconstruction as set forth in claim 6 wherein said other member has aninner peripheral means and an outer peripheral means, said opening meansbeing disposed intermediate said inner peripheral means and said outerperipheral means.
 8. A pulley construction as set forth in claim 6wherein said other member has an inner peripheral means and an outerperipheral means, said opening means comprising a plurality of slotsthat respectively interrupt one of said peripheral means of said othermember.
 9. A pulley construction as set forth in claim 2 wherein saidone member comprises said body member, said body member having an innerannular peripheral means provided with annular slot means therein thatcomprises said securing means thereof, said hub member having an outerannular peripheral means disposed in said slot means, said part of saidsecuring means of said body member bridging said slot means thereof. 10.A pulley construction as set forth in claim 9 wherein said hub membercomprises a flat disc-like plate.
 11. In a drive system comprising apulley construction, a shaft means, and a driven endless belt means,said pulley construction comprising a body member having a peripheralgroove means therein receiving part of said belt means therein andhaving securing means, and a hub member having securing means secured tosaid securing means of said body member so as to hold said members inaligned assembled relation to rotate in unison, said hub member havingmeans interconnected to said shaft means so that said pulleyconstruction and said shaft means will rotate in unison as said beltmeans drives said pulley construction, the improvement wherein saidsecuring means are so constructed and arranged that said securing meansof one of said members has a part thereof that is adapted to break awayfrom said one member under a certain normal driving force of said beltmeans when said shaft means is prevented from rotating so as to permitrelative rotational movement between said members while said securingmeans maintains the thus relatively rotating members in said alignedassembled relation thereof as said belt means continue to rotate saidbody member relative to said hub member.
 12. A drive system as set forthin claim 11 wherein said securing means of said other member comprisesopening means passing therethrough, said part of said securing means ofsaid one member extending through said opening means.
 13. A drive systemas set forth in claim 12 wherein said part of said securing means ofsaid one member is integral and one-piece with said one member.
 14. Adrive system as set forth in claim 13 wherein said one member is formedof rigid polymeric material.
 15. A drive system as set forth in claim 14wherein said one member comprises said body member.
 16. A drive systemas set forth in claim 12 wherein said opening means of said other membercomprises a plurality of spaced apart openings and said part of saidsecuring means of said one member comprises a plurality of partsrespectively extending through said openings.
 17. A drive system as setforth in claim 16 wherein said other member has an inner peripheralmeans and an outer peripheral means, said opening means being disposedintermediate said inner peripheral means and said outer peripheralmeans.
 18. A drive system as set forth in claim 16 wherein said othermember has an inner peripheral means and an outer peripheral means, saidopening means comprising a plurality of slots that respectivelyinterrupt one of said peripheral means of said other member.
 19. A drivesystem as set forth in claim 12 wherein said one member comprises saidbody member, said body member having an inner annular peripheral meansprovided with annular slot means therein that comprise said securingmeans thereof, said hub member having an outer annular peripheral meansdisposed in said slot means, said part of said securing means of saidbody member bridging said slot means thereof, said hub member comprisinga flat disc-like plate.
 20. In a method of making a pulley constructionfor use with an endless drive belt means, said method comprising thesteps of forming a body member with a peripheral groove means thereinfor receiving part of said belt means therein and with securing means,forming a hub member with securing means, securing said securing meansof said hub member to said securing means of said body member so as tohold said members in aligned assembled relation to rotate in unison, andforming said hub member with means for being interconnected to a shaftmeans so that said pulley construction and said shaft means will beadapted to rotate in unison, the improvement comprising the step offorming said securing means so that said securing means of one of saidmembers has a part thereof that is adapted to break away from said onemember under a certain normal driving force of said belt means when saidshaft means is prevented from rotating so as to permit relativerotational movement between said members while said securing meansmaintains the thus relatively rotatable members in said alignedassembled relation thereof.